Fault-Code Library · Camshaft sensing
P0340: Camshaft position sensor circuit, bank 1
The ECU is missing or cannot trust the camshaft position signal on bank 1.
Common symptoms
- •Long cranking
- •Reduced power
- •Rough running
- •Engine warning light
Likely causes
- •Failed camshaft sensor
- •Wiring or connector fault
- •Timing correlation issue
- •Oil contamination near sensor
First checks
- •Compare cam and crank synchronization data
- •Inspect connector and wiring
- •Check for related timing faults before replacing the sensor
Important
Cam sensor codes can be caused by real timing problems, so check correlation data.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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